Think Retina display Macs are a gimmick? Think again: Mac developer Gus Mueller is almost ready to pop out an update to the Acorn image editing app which will use the Retina display on the new MacBook Pro to spectacular (and rather useful) effect.

Amongst the other niceties involved in Retina-izing his app, Gus will be adding a “Retina Canvas” to Acorn 3.3. What’s that?

The interface elements of the app are all being redrawn at 2x resolution to look nice on screen, but the canvas will be drawn so that “1 pixel equals 1 physical dot on your hardware display.”

This means that the important part of the app – the image itself – should look, in Gus’s words, “freaken’ awesome on your Retina MBP.”

I think photo apps, and anything that uses a lot of text, will be the real winners with Mac Retina displays. I find it hard to even look at an ugly old iPad 2 now, let alone edit pictures, and I expect the same thing will happen once I take a good look at the new MacBook.

Can’t wait to see this awesome update in action? Good news! You don’t have to. There’s already a beta of Acorn 3.3 available for download.